battery light on

[pro321a]

New owner of a 2003 300a marauder. Previous owner had installed a new motorcraft battery and a new alternator(supposed to be a reman motorcraft unit,it does have a white regulator and the clutch pulley). Checked battery with my digital voltmeter,holds 12.6 volts, also checked battery voltage with car running and had 14.2 volts.
Charge light comes on after about 20 to 30 seconds after you start the car. Voltmeter inside car shows 14 volts. Any ideas? Thanks for any replies.

[fastblackmerc]

New owner of a 2003 300a marauder. Previous owner had installed a new motorcraft battery and a new alternator(supposed to be a reman motorcraft unit,it does have a white regulator and the clutch pulley). Checked battery with my digital voltmeter,holds 12.6 volts, also checked battery voltage with car running and had 14.2 volts.
Charge light comes on after about 20 to 30 seconds after you start the car. Voltmeter inside car shows 14 volts. Any ideas? Thanks for any replies.
Might have the wrong alternator installed.

[pro321a]

What can I use to identify if the correct one was installed? (I received no paperwork on the one the previous owner installed).

[fastblackmerc]

I don't know how to tell the difference. I believe it has to do with how the alternator interacts with the PCM. A Mustang alternator will fit but won't work properly..... as you can see.

Check rockauto.com for the correct part numbers from different manufacturers.